Add support for tracing via OpenCencus

This adds a few flags for configuring the tracer.
Includes support for jaeger tracing (built into OC).

vendor/go.opencensus.io/zpages/internal/gen.go

@@ -0,0 +1,19 @@
+// Copyright 2018, OpenCensus Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+package internal // import "go.opencensus.io/zpages/internal"
+
+// go get https://github.com/mjibson/esc.git
+//go:generate esc -pkg internal -o resources.go public/ templates/

vendor/go.opencensus.io/zpages/internal/resources.go

@@ -0,0 +1,284 @@
+// Code generated by "esc -pkg resources -o resources.go public/ templates/"; DO NOT EDIT.
+
+package internal
+
+import (
+	"bytes"
+	"compress/gzip"
+	"encoding/base64"
+	"io/ioutil"
+	"net/http"
+	"os"
+	"path"
+	"sync"
+	"time"
+)
+
+type _escLocalFS struct{}
+
+var _escLocal _escLocalFS
+
+type _escStaticFS struct{}
+
+var _escStatic _escStaticFS
+
+type _escDirectory struct {
+	fs   http.FileSystem
+	name string
+}
+
+type _escFile struct {
+	compressed string
+	size       int64
+	modtime    int64
+	local      string
+	isDir      bool
+
+	once sync.Once
+	data []byte
+	name string
+}
+
+func (_escLocalFS) Open(name string) (http.File, error) {
+	f, present := _escData[path.Clean(name)]
+	if !present {
+		return nil, os.ErrNotExist
+	}
+	return os.Open(f.local)
+}
+
+func (_escStaticFS) prepare(name string) (*_escFile, error) {
+	f, present := _escData[path.Clean(name)]
+	if !present {
+		return nil, os.ErrNotExist
+	}
+	var err error
+	f.once.Do(func() {
+		f.name = path.Base(name)
+		if f.size == 0 {
+			return
+		}
+		var gr *gzip.Reader
+		b64 := base64.NewDecoder(base64.StdEncoding, bytes.NewBufferString(f.compressed))
+		gr, err = gzip.NewReader(b64)
+		if err != nil {
+			return
+		}
+		f.data, err = ioutil.ReadAll(gr)
+	})
+	if err != nil {
+		return nil, err
+	}
+	return f, nil
+}
+
+func (fs _escStaticFS) Open(name string) (http.File, error) {
+	f, err := fs.prepare(name)
+	if err != nil {
+		return nil, err
+	}
+	return f.File()
+}
+
+func (dir _escDirectory) Open(name string) (http.File, error) {
+	return dir.fs.Open(dir.name + name)
+}
+
+func (f *_escFile) File() (http.File, error) {
+	type httpFile struct {
+		*bytes.Reader
+		*_escFile
+	}
+	return &httpFile{
+		Reader:   bytes.NewReader(f.data),
+		_escFile: f,
+	}, nil
+}
+
+func (f *_escFile) Close() error {
+	return nil
+}
+
+func (f *_escFile) Readdir(count int) ([]os.FileInfo, error) {
+	return nil, nil
+}
+
+func (f *_escFile) Stat() (os.FileInfo, error) {
+	return f, nil
+}
+
+func (f *_escFile) Name() string {
+	return f.name
+}
+
+func (f *_escFile) Size() int64 {
+	return f.size
+}
+
+func (f *_escFile) Mode() os.FileMode {
+	return 0
+}
+
+func (f *_escFile) ModTime() time.Time {
+	return time.Unix(f.modtime, 0)
+}
+
+func (f *_escFile) IsDir() bool {
+	return f.isDir
+}
+
+func (f *_escFile) Sys() interface{} {
+	return f
+}
+
+// FS returns a http.Filesystem for the embedded assets. If useLocal is true,
+// the filesystem's contents are instead used.
+func FS(useLocal bool) http.FileSystem {
+	if useLocal {
+		return _escLocal
+	}
+	return _escStatic
+}
+
+// Dir returns a http.Filesystem for the embedded assets on a given prefix dir.
+// If useLocal is true, the filesystem's contents are instead used.
+func Dir(useLocal bool, name string) http.FileSystem {
+	if useLocal {
+		return _escDirectory{fs: _escLocal, name: name}
+	}
+	return _escDirectory{fs: _escStatic, name: name}
+}
+
+// FSByte returns the named file from the embedded assets. If useLocal is
+// true, the filesystem's contents are instead used.
+func FSByte(useLocal bool, name string) ([]byte, error) {
+	if useLocal {
+		f, err := _escLocal.Open(name)
+		if err != nil {
+			return nil, err
+		}
+		b, err := ioutil.ReadAll(f)
+		_ = f.Close()
+		return b, err
+	}
+	f, err := _escStatic.prepare(name)
+	if err != nil {
+		return nil, err
+	}
+	return f.data, nil
+}
+
+// FSMustByte is the same as FSByte, but panics if name is not present.
+func FSMustByte(useLocal bool, name string) []byte {
+	b, err := FSByte(useLocal, name)
+	if err != nil {
+		panic(err)
+	}
+	return b
+}
+
+// FSString is the string version of FSByte.
+func FSString(useLocal bool, name string) (string, error) {
+	b, err := FSByte(useLocal, name)
+	return string(b), err
+}
+
+// FSMustString is the string version of FSMustByte.
+func FSMustString(useLocal bool, name string) string {
+	return string(FSMustByte(useLocal, name))
+}
+
+var _escData = map[string]*_escFile{
+
+	"/public/opencensus.css": {
+		local:   "public/opencensus.css",
+		size:    0,
+		modtime: 1519153040,
+		compressed: `
+H4sIAAAAAAAC/wEAAP//AAAAAAAAAAA=
+`,
+	},
+
+	"/templates/footer.html": {
+		local:   "templates/footer.html",
+		size:    16,
+		modtime: 1519153248,
+		compressed: `
+H4sIAAAAAAAC/7LRT8pPqbTjstHPKMnNseMCBAAA//8ATCBFEAAAAA==
+`,
+	},
+
+	"/templates/header.html": {
+		local:   "templates/header.html",
+		size:    523,
+		modtime: 1519164535,
+		compressed: `
+H4sIAAAAAAAC/5TRv07rMBQG8D1P4ev1qvat7oKQEwZgYEAwdGF0nZP4UP+JfE6oqqrvjkyKBGIpky0f
++6fP+syfu6fbzcvzvfAcQ9eYuohg09hKSLIzHmzfNUIIYSKwFc7bQsCtnHlYXcnziJEDdMej2tTN6WT0
+crJMA6adKBBaST4XdjMLdDlJ4QsMrdR6v9+rPEFykGgmhVkP9q1eUeiy1D8ZPgQgD8CfxjRvAzr9BXFE
+F730zBNdaz3kxKTGnMcAdkJSLkddM9wMNmI4tI+WoaANfx9cTiR/QbvcgxqBYx/q39bqv/qn45lTmHoc
+82rCtFMR00fwM06u4MSihwGKoOIuJSvzSrIzehG6xuilSLPN/aHWvP7Wll93zXsAAAD//6iqQ1ULAgAA
+`,
+	},
+
+	"/templates/rpcz.html": {
+		local:   "templates/rpcz.html",
+		size:    2626,
+		modtime: 1519164559,
+		compressed: `
+H4sIAAAAAAAC/+yW3WrbMBTH7/0UwmUjYyxJU3o1W1C6sQ4WNrq+gCwdfzBFMtJx9+Hl3cex3DhNCrOz
+XfbGxFZ+5/8D+Ry5bZ0wBbD5VxT4wdmm9tttlNQ8QZFpYFkhrbYuPQMAyHP2vVJYpufL5QueoGNCV4VJ
+JRgExxNUPMmtQearX5C+XvG2nb+rHEisrNlukwUt8mRB/1ugowuF8GRR8+ggMD7L8/wSIGa5ExtIM/uD
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+2F5240elDlynO5kKwjtspO3tl2sa6r2qEwijYnusM50KBdE9aqRqd4DsySqBYnT2Du6UT0OD+AE7Uj6c
+YKfaD/R0/YH9F/9wiE5uv4BN7L8A/a0BwxxqWzCKPg37b7bdgz8BAAD//6NjPmJCCgAA
+`,
+	},
+
+	"/templates/summary.html": {
+		local:   "templates/summary.html",
+		size:    1619,
+		modtime: 1519164559,
+		compressed: `
+H4sIAAAAAAAC/6yVPW/bMBCG9/yKg2p4qu2kW12JRQtkCzok3YoOlHSWBdMngaSc2iz/e8EP+Stqi8Re
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+/o6e0J9Pge+G+dv98tClYlxs6IcDbPDW/wGpE8cGfB2Iiij9kHnIdOY/JezmTwAAAP//Dz6TJ1MGAAA=
+`,
+	},
+
+	"/templates/traces.html": {
+		local:   "templates/traces.html",
+		size:    420,
+		modtime: 1519164578,
+		compressed: `
+H4sIAAAAAAAC/4yQsU70MBCEez/FKtIv3RW/w6WgOIw7kGgoDiRqO14gwnGM1xEgs++OnKMA5Qq2ssYz
+I82nolZW30UT4NaMuIdSZH0wg2qtVm3UQkVd1XlkhgO+zkiZvj8SavHwjAFO35U3kdDBhrDfiv9/PFFK
+MuEJQR6mN2IuJaYh5Edo/nXn1MBmCA7fQV4P6B3B2ZYZfnh23dqzO3p+i12tlp85mR4HxyxKweCYVbvs
+UjYt25UFyh8eL5t+8lPaWz/jRaPva+zGVUowogkEZMbo0UE6MpKiIlinTf9yMh6mvKpYMH8FAAD//yQs
+JUakAQAA
+`,
+	},
+
+	"/": {
+		isDir: true,
+		local: "",
+	},
+
+	"/public": {
+		isDir: true,
+		local: "public",
+	},
+
+	"/templates": {
+		isDir: true,
+		local: "templates",
+	},
+}